open_game

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full behavioral burden. It does disclose a real side effect (scanning for .pak/.ucas/.utoc files), which is useful, but says nothing about whether this opens a stateful session, whether later tools depend on it, or what permissions/state are required. That is a significant gap for a stateful loader tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences, the core action front-loaded, and the scan targets appended as supporting detail. No filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no annotations and no output schema, the definition is only partially complete: an agent cannot tell whether opening returns a session handle, whether it must precede read_asset/list_assets, or how errors (missing key, no .pak found) surface. The scan behavior is covered, but session/return context is not.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so the schema already explains game_path, aes_key, and ue_version. The description adds no format, default, or interaction detail beyond that, so the baseline of 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ("Open a game directory") and narrows the scope to "Unreal asset reading", with the scan targets (.pak/.ucas/.utoc) making the intent concrete. It is distinguishable from Unity/JAR/PE siblings by the Unreal file formats, but it never names a related sibling like load_game or detect_engine, so differentiation is implied rather than explicit.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no when-to-use framing, no prerequisites (must an AES key or detected engine exist first?), and no mention of alternatives such as load_game or unpack_game. The only guidance is the implicit signal that opening precedes reading assets.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.